The present invention relates generally to mobile telephony communications; and more specifically to the ability to store in the network a catalogue of multiple identities from several networks owned by the same person which can be accessed from any mobile phone on any of the networks.
The use of a Subscriber Identity Module (SIM) which is an active card plugged into a Mobile Station (MS) with a unique identity called the International Mobile Equipment Entity (IMEI) which is allocated a unique directory number called the Mobile Station International ISDN number (MSISDN) is well documented is 3GPP/ETSI GSM specifications such as 3GPP/ETSI GSM 02.17 (SIM-Functional Characteristics) and 3GPP/ETSI GSM 02.16 (International Mobile Station Equipment Identities (IMEI)). The paring of the IMSI and MSISDN is stored together with other information relating to the subscriber in the Home Location Register (HLR) which is located in the home network of the subscriber. The system comprises Visitor Location Register (VLR) and Mobile Switching Centre (MSC). Information of active visitor MSs is stored in the VLR.
In this scenario the mobile number of the user is fixed to the MS. This has the disadvantage that if multiple people use the same phone, or if the user has several mobile phone numbers, either on the same network or across several networks and countries, they cannot co-exist on the same MS at the same time.
Users can swap their identities by changing the SIM card in the MS, a process which involves removing the case of the MS and battery, physically swapping the SIM cards and replacing the battery and case. In this scenario only one identity is active, and the original SIM card is off network. Any voice calls made to the original MSISDN will be either sent to voicemail, or the dialling party will hear a message indicating that the subscriber is not available depending on the subscriber's settings. All messages including Short Message Service (SMS) will be stored in the appropriate message centre such as the Short Message Service Centre (SMSC) and will be delivered on the original SIM is re-activated on the network.
In US patent U.S. Pat. No. 6,212,372 B1 Julin provided a method and apparatus to provide at least two identities on each SIM card on the MS. The identity could be swapped either by the subscriber physically altering the SIM card, for example by reinserting the SIM card upside down, or by an application installed on the MS.
In US Patent Application US 2007/0213050 A1 Jiang provided a method and apparatus to provide multiple identities across several networks, however the subscriber has to carry a special SIM card with a SIM Tool-Kit (STK) application which enables the SIM to carry multiple IMSIs and causes the handset to register with an alternative local MSISDNs.
In the inventors application Ser. No. 12/214,902, Method and System for Enabling Personalised Shared Mobile Phone Usage, Application Filed Mar. 4, 2008, a method and system to enable a user to used any shared MS in the network and access a virtual account to make and receive voice calls and SMSs was described. This approach transforms the MS into a thin client which accesses a virtual identity stored in a system server (called MXShare) acting as an HLR on the network. The virtual identity comprised an MSISDN and virtual IMSI stored on the MXShare server and the system allows calls to be made and received on the shared MS. This system has the restriction that using Unstructured Supplementary Service Data (USSD) as the communication channel for the thin client; the MS and virtual IMSI have to be registered on the same mobile network to be fully functional. This is because any USSD commands sent from the MS to activate and control the virtual identity are sent to the home network of the MS/SIM combination for interpretation, in this case the output being that the commands entered into the USSD strings are dispatched to MXShare for interpretation and action.
In the preferred embodiment of the system described previously, mobile operators can service people who cannot afford a phone, or do not wish to purchase a phone, and still allow them to have a fully functioning pre-paid account which they access using other people's phones, or street side mobile pay phones. In alternative embodiments it can be used to service people who already have a handset, and a mobile phone number, but require virtual access to their account from another phone, or where a user has multiple phone numbers on the same network and wishes to use them from one specific handset.
Many people may own separate SIMs for different networks within a country, in order to use the best available tariff when making a specific outbound call. When people travel between countries they may own SIMs across multiple countries. The issues described previously still exist and are made more difficult when dealing with different countries. For example a subscriber may not be able to access any service on a particular SIM at all in the different country if no roaming agreements exists, and if they have not forwarded their phone before leaving they may not be able to receive any calls until they return to that country. If a subscriber does not use a particular prepaid account and SIM for any length of time, typically 3 months, the number may be recycled and given to a new subscriber and the user will lose any airtime credit they may have.
Thus there is a need to be able to manage different identities across different networks without the hassle of removing the SIM card, whilst ensuring that the identities are active at the same time. Prior art has shown how this can be done using a special SIM card, however the present application shows how this can be done without the need to change the SIM card.